This invention relates generally to the field of data transmission systems, and in particular, to a system, apparatus and method for reducing facsimile (fax) transmission status outcalls by a receiving Fax-to-SMTP gateway to a remote fax device upon the gateway receiving responses to at least two confirmation request messages.
The transmission of facsimiles is a very popular mechanism for the transfer of information. It has been a standard of transferring information for many years. Fax transmissions are often used for sending textual documents, drawings, illustrations, music sheets, and other information fixed on a piece of paper or stored in memory as an electronic file. More recently, electronic mail (e-mail) has become another popular mechanism for the transfer of information. Because the use of e-mail has become widely prevalent recently, more information has been transferred between network equipment through the use of e-mail. For example, word processing application files are now readily transferred between email users, as are Internet web files in the form of Hyper Text Markup Language xe2x80x98HTMLxe2x80x99.
Recently, there has been a need to merge facsimile and e-mail transmissions. For instance, fax information can now be transmitted as an attachment to an e-mail message to other equipment that accepts reception of faxes. A personal computer (PC) can be set up to send an email message having attached thereto a facsimile file, which may be transmitted through the Internet to another PC having fax and modem capability or, alternatively, to another fax machine. One standard protocol employed in the industry for the transmission of a facsimile file with e-mail is to format the facsimile file in accordance with the Tagged Image File Format (TIFF).
FIG. 1 illustrates a block diagram of an example prior art fax-over-email communication system 10 for the generation and transmission of email with an attached TIFF file. The system comprises a sending fax machine 12 and a standard FAX-to-SMTP gateway 14 (SMTP stands for xe2x80x9cSimple Mail Transfer Protocolxe2x80x9d) at a sending end of the system 10. The fax-over-email communication system 10 also includes a plurality of mail servers (also known as SMTP servers or Mail Transfer Agents (mailers)), six of which are shown in FIG. 1 by example as mailers having respective even reference numbers 16-26 associated therewith. The system 10 further includes a FAX-to-SMTP gateway 28 and a fax machine 30 at a receiving end thereof. The sending and receiving fax machines 12 and 30 are coupled to respective FAX-to-SMTP gateways 14 and 28 by public switch telephone network (PSTN) interfaces 32 and 34. The FAX-to-SMTP gateways 14 and 28 are coupled respectively to mailer 16 and mailer 26 by respective communication links 36 and 38. The communication links 36 and 38 cause coupling between the gateways and the mailers pursuant to any protocol that enable ingress and egress mailers to communicate to SMTP gateways. An example of such a protocol is the Transmission Control Protocol/Internet Protocol (TCP/IP). Also, the mailers 16-26 are coupled to each other by respective communication links 40a-e, which may also use any protocol capable of effectuating such communications such as the TCP/IP protocol. It should be noted that the protocol employed for establishing communications between the mails need not necessarily be the same protocol employed in establishing communications between the gateways and mailers.
The fax-over-email communication system 10 is shown merely to illustrate how, in the prior art, a standard fax message in compliance with the T.30 protocol is sent from the sending fax machine 12 to the receiving fax machine 30, whereby the fax message is communicated through the system by way of an email message having an attached TIFF file. First, a standard fax transmission (fax message) 42 is generated by the sending fax machine 12 and delivered to the standard FAX-to-SMTP gateway 14 by way of communication interface 32. The FAX-to-SMTP gateway 14 converts the standard fax message into a TIFF file and thereafter attaches the TIFF file to an e-mail message 44. The e-mail message 44 is then transferred through the communication link 36 using the TCP/IP protocol. The email message 44 is then relayed from mailer 16 to mailer 26 by way of the other intermediate mailers 18-24 and communication links 40a-e, also using the TCP/IP protocol. Thereafter, the receiving FAX-to-SMTP gateway 28 receives the email message 44 from mailer 26 through communication link 38. The FAX-to-SMTP gateway 28 then detaches the TIFF file from the email message 44 and converts the TIFF file into the fax message 42. The fax message 42 is subsequently delivered to the receiving fax machine 30.
After the receiving fax machine 30 receives the fax message 42, it is typically desired that the receiving FAX-to-SMTP gateway 28 send back a confirmation message to inform the user at the sending fax machine 12 that the fax message 42 was successfully delivered to the receiving fax machine 30. In the prior art, the sending FAX-to-SMTP gateway 14 is configured to send a confirmation request message along with the email message 44 to the receiving FAX-to-SMTP gateway 28 by way of the mailers 16-26. There are two standard confirmation request messages that are typically generated and sent in order to obtain a status as to the delivery of the fax message 42. One is a delivery status notification (DSN) message specified in protocol RFC1891 issued by the Internet Engineering Task Force (IETF), and the other is a message disposition notification (MDN) specified in protocol RFC2298 also issued by the IETF.
The sending FAX-to-SMTP gateway 14 may be configured to send either a DSN confirmation request message, or an MDN confirmation request message, or both. It is desirable to send both the DSN and the MDN messages in order to better ensure the accuracy of the confirmation. In other words, sending both the DSN and the MDN confirmation request messages increases the likelihood that a confirmation response to these messages will be returned back to the sending FAX-to-SMTP gateway 14. The DSN confirmation request is transmitted with the email message 44 as an part of the email message""s extension. Each of the mailers 16-26 must have DSN capability so as to propagate the DSN confirmation request to the next mailer. If not, the DSN confirmation request will not propagate to the receiving FAX-to-SMTP gateway 28 while the email message 44 does so propagate.
In one prior art system, only MDNs (and not DSNs) are sent. This poses a problem however, in that the recipient may be configured to ignore the MDN request or it could be unable to understand the MDN request. In fact, users of such prior art systems are finding that some recipients cannot or will not respond to their MDN requests.
The MDN confirmation request is part of the email message""s header information, as specified by the RFC822 protocol, and appears to the mailers as a block of data. Additionally, the MDN confirmation request does not require special support or capabilities for intermediate mailers, thus, the recipient, i.e. the FAX-to-SMTP gateway 28, receives the MDN confirmation request as part of the mail message itself. The MDN request is more likely than a DSN to arrive at the recipient because MDNs do not require support of intermediate mailers, whereas, DSNs do require support of intermediate mailers.
A recipient need not be a gateway; another example of a recipient is a Personal Computer (PC) as shown in dashed-lines. It is important to note that in using a PC, the mail software program, which may be one of a variety of commercially-available software programs such as Novell Groupwise, Microsoft Outlook, Netscape mailer, that generally resides in PCs in PCs for reading email applications need not be modified in accordance with the present invention.
There are five possible responses to a DSN confirmation request. First, the sending FAX-to-SMTP gateway 14 may receive a xe2x80x9cRelay DSNxe2x80x9d response which signifies that one of the mailers 16-28 along the path does not have DSN capability. In this case, the mailer immediately preceding the DSN-incompatible mailer receives the email message 44 and sends back the xe2x80x9cRelay DSNxe2x80x9d to the sending FAX-to-SMTP gateway 14. This mailer then passes the email message 44 to the DSN-incompatible mailer for transmission to other enroute mailers along the path to the receiving FAX-to-SMTP gateway 28. Second, the sending FAX-to-SMTP gateway 14 may receive a xe2x80x9cDelivery Successxe2x80x9d response if the DSN confirmation request message reaches the receiving FAX-to-SMTP gateway 28 and the gateway 28 issues the xe2x80x9cDelivery Successxe2x80x9d response indicating that the fax message 42 was successfully delivered to the receiving fax machine 30. Other types of DSN responses are discussed in a document entitled RFC1894.
Third, the sending FAX-to-SMTP gateway 14 may receive a xe2x80x9cDelivery Failurexe2x80x9d response which signifies that there was no successful disposition of the fax message 42. This situation would likely be due to an invalid telephone number or an unauthorized telephone connection. Fourth, the sending FAX-to-SMTP gateway 14 may receive a xe2x80x9cDelayed Deliveryxe2x80x9d response which signifies that one of the mailers did not successfully deliver the DSN message within a pre-determined length of time dictated by the mailer generating the xe2x80x9cDelayed Deliveryxe2x80x9d response. The xe2x80x9cDelayed Deliveryxe2x80x9d response is an option that can be requested by a user at the sending end of the system 10. It the user does not request a xe2x80x9cDelayed Deliveryxe2x80x9d response, it will not be generated by an mailer, and thus, not received by the sending FAX-to-SMTP 14.
The fifth type of DSN response, an xe2x80x98expandedxe2x80x99 DSN message, indicates that multiple recipients are going to receive the message, which may cause multiple MDNs to be generated (and sent to the original fax sender). While this (multiple outdials) is undesirable, the sender cannot know how many recipients there are and therefore, the sender cannot reliably know if xe2x80x9callxe2x80x9d recipients have received the message.
As previously stated, the MDN confirmation request message is part of the header of the email message (as previously noted, the confirmation request is part of the original message itself while the delivery confirmation message is a separate message). Accordingly, it looks merely as a block of data to an mailer. It follows then that if the email message 44 reaches the receiving FAX-to-SMTP gateway 28, then the MDN confirmation request also reaches the gateway 28. Although, the MDN confirmation request reaches the receiving FAX-to-SMTP gateway 28 under normal conditions, a response to the MDN confirmation request may not be generated, unless the receiving FAX-to-SMTP gateway 28 or the email recipient is configured to send such a message. In other words, generating and sending a response to an MDN confirmation request message is optional, which a user at the receiving FAX-to-SMTP gateway 28 can enable or disable. If such an option is enabled, then a response to the MDN message is sent back to the sending FAX-to-SMTP gateway 14 indicating that the fax message 42 was successfully transmitted to the receiving fax machine 3.
The sending FAX-to-SMTP gateway 14 uses these responses to the DSN and MDN confirmation request messages to inform the user at the sending fax machine 12 of the status of the transmission of the fax message 42. For instance, if the receiving FAX-to-SMTP gateway 14 receives a xe2x80x9cRelay DSNxe2x80x9d response, the gateway 14 makes an outcall to the sending fax machine 12 notifying it that the DSN confirmation request message was not delivered to the receiving FAX-to-SMTP gateway 28 because one of the mailers is not DSN-compatible. If the sending FAX-to-SMTP gateway 14 receives a xe2x80x9cDelivery Successxe2x80x9d response, the gateway 14 makes an outcall to the sending facsimile device 12 notifying it that the DSN confirmation request message was delivered by the receiving FAX-to-SMTP gateway 28, and that the fax message 42 was successfully delivered to the receiving facsimile device 30. If the FAX-to-SMTP gateway 14 receives an MDN response, the gateway 14 makes an outcall to the sending facsimile device 12 notifying it that the fax message 42 was successfully delivered to the receiving facsimile device 30.
One drawback of the prior art fax-over-email communication system 10 stems from the fact that the sending FAX-to-SMTP gateway 14 sends two confirmation request messages and makes an outcall to the sending fax machine 12 each time the gateway 14 receives a confirmation request response.
As the reader may recall, it is important that both DSNs and MDNs confirmations are made. Sending solely an MDN request may not be sufficient, at times, because some recipients cannot or will not respond to their MDN requests. Thus, sending both a DSN and MDN request is the only way to ensure that the sender receives indication of successful delivery of its message.
Accordingly, it is often the case that the sending FAX-to-SMTP gateway 14 makes two outcalls to the sending fax machine 12, one for receipt of a response to the DSN confirmation request message and another for the receipt of a response to the MDN confirmation request message. For example, the gateway 14 may receive a DSN response and also an MDN response at different times, causing the gateway 14 to make two outcalls to the sending facsimile device 12. The drawback lies in that some of the sending fax machines 12 may be in a different telephone area code or even in a different country. Thus, each outcall from the gateway 14 to the facsimile device 12 is expensive. It is therefore undesirable to make multiple outcalls from the gateway 14 to the fax machine 12 due to an increase in telephone call charges.
Another drawback of the prior art fax-over-email communication system 10 is that the user at the sending facsimile device 12 may be confused by multiple and different responses received for the same transmitted fax message 42. For example, assume that the sending FAX-to-SMTP gateway 14 sends both DSN and MDN messages to the receiving FAX-to-SMTP gateway 28 by way of the mailers 16-26. If one of the mailers is not DSN compatible, a xe2x80x9cRelay DSNxe2x80x9d is sent back to the sending FAX-to-SMTP gateway 14. In response to the xe2x80x9cRelay DSNxe2x80x9d, the sending FAX-to-SMTP gateway makes an outcall to the sending fax machine 12 notifying it that the DSN confirmation response was not received. A short time later, the sending FAX-to-SMTP gateway 14 receives an MDN response, and makes another outcall to the sending fax machine 12 informing the user of a successful fax message delivery. The user at the sending facsimile device 12 may get confused due to the discrepancy between the confirmation printed by their own fax machine and the DSN and the MDN responses. In addition, because two confirmations have been generated at the sending fax machine 12 at possibly substantially different times, logistically it becomes a burden to properly place the paper confirmations with the transmitted document. Furthermore, there is additional communications cost to the user for having to make two confirmation calls.
To reiterate, the prior art fax-to-SMTP gateway 14 makes an outcall to the sending facsimile device 12 each time a response to a DSN and MDN confirmation request message is received. In many instances, the prior art fax-to-SMTP gateway 14 receives multiple responses, such as a DSN response and an MDN response. In such a case, the prior art fax-to-SMTP gateway 14 makes two outcalls to the sending facsimile device 12, which may be located in a different telephone area code or in a different country. Such a call is expensive, and making two of them, is doubly so. In addition, in certain situations, the DSN and the MDN responses may indicate a different result, such as when the gateway receives a xe2x80x9cRelayed DSNxe2x80x9d and an MDN response. In this case, the user at the sending facsimile device 12 may become confused. Finally, the DSN and the MDN responses may be received by the gateway 14 at substantially different times. Thus, two confirmations are generated at the sending facsimile device 12 at substantially different times which can cause logistic problems with duplicate paperwork. As previously noted, both DSN and MDN requests are necessary.
Thus, there is a need for a system, apparatus and method for notifying a user at a sending facsimile device of the delivery status of its outgoing facsimile messages without having the corresponding FAX-to-SMTP gateway 14 make a plurality of outcalls, which leads to undue operating costs, contusion, and logistic problems.
Briefly, an embodiment of the present invention for use in a communication system for transmission of facsimile (fax) information using an email message from a sending fax device used by a sending fax user to a receiving fax device used by a receiving fax user includes a sending gateway device coupled to the sending fax device for causing transfer of a fax message received from the fax device. The sending gateway device further attaches the transferred fax message to an email message. The at least one of the mailer devices is coupled to a receiving gateway device and is further coupled to the sending gateway device for receiving the email message and transferring the same to the receiving gateway device. The receiving gateway device is coupled to the receiving fax device for detaching the fax information from the transferred email message and coupling the detached fax information, through a receiving communication link, to the receiving fax device for use by the receiving fax user. The sending gateway device receives a particular fax message and prepares an email message having attached thereto the particular fax message and transmits the prepared email message along with a first and a second confirmation requests to the receiving gateway device through the mailer device. The first confirmation request corresponds to a first response and the second confirmation request corresponds to a second response. Upon receipt of a first response to the first confirmation request, the sending gateway device awaits a predetermined length of time for a response to the second confirmation request and upon receipt of a response to the second confirmation request, the sending gateway device places an outcall to the sending fax device. In accordance with the teachings of the present invention, multiple outcalls for confirming the status of the fax message transmission are avoided thereby reducing costs to the sending fax user and further reducing the likelihood of confusion and logistic problems to the sending fax user.